Is it true that eggs raise cholesterol?

There is an opinion that eating chicken eggs is harmful because they contain a large amount of cholesterol. We decided to check whether these fears have any basis.

Information that an egg is a “cholesterol bomb” can be found in women’s magazines. IN blogs They write about proper nutrition that they help increase cholesterol levels. In sports publications It is advised to limit the consumption of eggs if a person’s cholesterol is already high. And on some websites about the food it is stated that it is a “very harmful product.” The question of whether eggs are harmful is asked by many authors. popular science, culinary And glossy publications, as well as portalsdedicated to a healthy lifestyle. In some media warn from eating eggs without heat treatment, supposedly this way they increase cholesterol more.

Eggs - one of the most accessible sources of protein. In addition, they contained many other useful substances: omega-3, folic acid, vitamins A, K, E, B12, selenium, calcium, phosphorus, biotin, etc. In addition, egg yolks actually contain contained a large amount of cholesterol.

High cholesterol increases risk of heart disease and stroke. However, not all cholesterol is equally harmful. Scientists differentiate two types of this substance:

• LDL (low-density lipoprotein), also called bad cholesterol. It makes up most of the cholesterol in the body. It is this substance that accumulates on the walls of blood vessels and increases the risk of disease;
• HDL (high density lipoprotein), or good cholesterol. It carries cholesterol to the liver, which then flushes it out of the body. High levels of such cholesterol, on the contrary, reduce the risk of heart disease and stroke.

Since good cholesterol helps eliminate bad cholesterol, what is important is not the total content of this substance in the blood, but the correct ratio there are two types of it. It is this factor that determines high or low cholesterol levels.

Cholesterol 80% is produced by our liver and intestines and only 20% enters the body from food. To produce bad cholesterol and reduce good cholesterol for the most part influence saturated fats and trans fats in food, and not dietary (that is, coming from food) cholesterol. It is them, unlike eggs, that are usually advise avoid medical organizations. Such fats are found in bakery and confectionery products, chips, fast food, and fried foods.

Nevertheless, for quite a long time there was an opinion: since eggs contain cholesterol, they are harmful and it is advisable to exclude them from the diet. In this regard, many research, most of which did not find a significant relationship between eating eggs in reasonable quantities (one or two per day) and blood cholesterol levels. Harvard Medical School experts, citing their own research and patient observations, also claimthat eating one egg a day does not increase the risk of cardiovascular disease.

In 2015, a team of Australian scientists conducted a three-month study, in which 140 participants were divided into two groups: one ate two eggs six times a week, and the other ate less than two eggs a week. As a result of significant differences in lipid profile (a set of indicators - levels of HDL, LDL, total cholesterol and triglycerides in the blood) no participants were identified.

To the same conclusion came Chinese researchers who monitored the diet of more than 7,000 Chinese residents for several years. There was no difference in arterial health between those who ate a lot of eggs and those who ate very few eggs. In addition, moderate consumption of eggs (about three to four per week) has been shown to have beneficial effects on arterial health.

American scientists who conducted research in 2020 meta-analysis Modern scientific research on this topic also came to the conclusion: there is no serious evidence that eggs in the diet increase the risk of cardiovascular disease in healthy people. However, they note that more research is needed on the effect of eating eggs for people with diabetes.

Similar research were carried out and during the 2012–2016 Korean National Health and Nutrition Examination Survey. It turned out that dietary cholesterol did not seriously affect blood cholesterol levels.

Participants of the 13-week experiment Department of Food Science at the University of Connecticut consumed three eggs per day. As a result, the researchers recorded no changes in their LDL/HDL ratio, a key indicator affecting the risk of cardiovascular disease. During another experiment The same Department of Food Science divided participants into two groups and gave them either oatmeal or two eggs for breakfast. After four weeks of this diet, the LDL/HDL ratio remained unchanged in both groups. Scientists from Denmark came to the conclusion that genetics, diet in general and physical activity have a greater influence on the likelihood of developing heart and vascular diseases than eggs.

One of the largest international studies, which covered 177,000 people from 50 countries, also did not reveal any evidence linking egg consumption to cardiovascular disease risks, blood lipid profiles or causes of death.

There are, however, studies whose results are not in favor of eggs. So, for example, American study of older women's diets, health conditions and causes of death (the study spanned nearly 19 years) found that those who ate one egg per day or more were more likely to have cardiovascular disease than those who ate less than one egg per week. At the same time, scientists define the risk as moderately high.

Chinese researchers also published results from another long-term follow-up of more than 500,000 US residents. The study began in 1995, recruiting participants ages 50 to 71, and ended in 2011. Those who reported eating eggs frequently in their food diaries were more likely to have heart disease and cancer.

American scientists, in another long-term study, the average age of the participants at the start of observations was 51 years old, installedthat every additional 300 mg of dietary cholesterol significantly increases the risk of cardiovascular disease. Doctors really recommend do not eat more than 300 mg of cholesterol per day (for comparison, in one large egg - 185 mg).

Japanese researchers who studied the diet of their compatriots not identified no relationship between eating moderate amounts of eggs and cholesterol levels, although they note that compared to Americans, the Japanese overall eat fewer foods that contain or affect cholesterol production, so they have some head start.

Slight increase in risk of coronary heart disease with one egg daily showed another American study conducted among US veterans, whose average age was 64.4 years. As you can see, most of the studies that found a relationship between egg consumption, cholesterol levels and the risk of heart disease involved older people, who appear to be at risk. One more risk group - people with type 2 diabetes.

National Heart Foundation of New Zealand recommends people with a predisposition to cardiovascular diseases should eat no more than six eggs per week (this amount, according to experts, should not have a serious impact on health); for healthy people there are no separate recommendations on the amount, but it is indicated that eggs can be included in the diet. The American Heart Association also believes It is quite safe to eat one egg per day.

At the same time, doctors remind, that it is important to watch how you cook eggs and what you use them with. So, fried eggs with bacon and bread and butter can really have a serious effect on your cholesterol levels, but not at all due to the cholesterol content in the eggs.

Thus, most researchers agree that young, healthy people can eat one or two eggs a day without any consequences for their cholesterol levels. However, it is worth watching your diet: if you eat a lot of other foods that contain or contribute to cholesterol production, it may be worth reducing the amount of eggs in your diet. Not least of all, this applies to those products that are traditionally eaten for breakfast along with eggs: bacon, butter, bread. People who are predisposed to cardiovascular diseases, diabetics, and the elderly should be more careful in consuming eggs, as, according to some studies, it may have a negative impact on the health of these groups. At the same time, eggs are a healthy and nutritious product, so you shouldn’t give them up completely.

Half-truth

What do our verdicts mean?

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